LTD exhaust upgrade

I've been looking to upgrade my exhaust ideally keeping it simple. I've been looking for a catback system but all I can find is stuff built to OE on a few websites. I'm pretty new to doing stuff on my car apart from oil changes and wanted to see if anyone had any opinions

Define "upgrade".
There are things you can do, pretty much all Fox Body shorties fit, some Fox Body X and H pipes fit.
Most larger piping is 2.5" and will be way too much for a stock panther 302.

Overall larger piping so its the stock 4 cat that has a y merge with 2" pipes, so what I was looking at was possible going from the stock 2" manifolds to 1 cat per side and have the output be 2 1/4 I'm not looking for anything crazy and this is the first thing that wouldn't be stock about her I wanna free up some air, a little power and some noise. Crown vice are heavy the last thing something heavy needs is to also be asthematic. She's a 1988 Ltd lx with a 5.0 completely stock